Dual-function catheter handle

ABSTRACT

A dual function catheter handle for simultaneous movement of two control wires has a handle housing having a core with a longitudinal slot mounted in its interior. A first moveable member is provided with a proximal end mounted in the interior of the handle housing and a distal end extending outside the handle housing. The first moveable member is longitudinally moveable relative to the handle housing. A second moveable member is mounted in the longitudinal slot of the core and is longitudinally moveable relative to the core and handle housing. A rotatable member is mounted on the handle housing and has a threaded inner surface that mates with a threaded surface of the second moveable member so that rotation of the rotatable member causes longitudinal movement of the second moveable member. The first and second moveable members can simultaneously move proximally relative to the handle housing.

CROSS-REFERENCE TO RELATED APPLICATION(S)

This application is a divisional application of U.S. patent applicationSer. No. 11/173,105, filed Jul. 1, 2005 now U.S. Pat. No. 7,503,914,entitled DUAL FUNCTION CATHETER HANDLE, which is a continuation of U.S.patent application Ser. No. 10/040,981, filed Dec. 31, 2001 now U.S.Pat. No. 6,913,594, entitled DUAL-FUNCTION CATHETER HANDLE, the entiredisclosures of which are incorporated herein by reference.

FIELD OF THE INVENTION

The present invention is directed to a dual-function catheter handle formanipulating two different control wires.

BACKGROUND OF THE INVENTION

Electrode catheters have been in common use in medical practice for manyyears. They are used to stimulate and map electrical activity in theheart and to ablate sites of aberrant electrical activity.

In use, the electrode catheter is inserted into a major vein or artery,e.g., femoral artery, and then guided into the chamber of the heartwhich is of concern. Within the heart, the ability to control the exactposition and orientation of the catheter tip is critical and largelydetermines how useful the catheter is.

Steerable catheters are generally well-known. For example, U.S. Pat. No.RE 34,502 describes a catheter having a control handle comprising ahousing having a piston chamber at its distal end. A piston is mountedin the piston chamber and is afforded lengthwise movement. The proximalend of the catheter body is attached to the piston. A puller wire isattached to the housing and extends through the piston and through thecatheter body. The distal end of the puller wire is anchored in the tipsection of the catheter. In this arrangement, lengthwise movement of thepiston relative to the housing results in deflection of the distal endof the catheter body. The design described in RE 34,502 is generallylimited to a catheter having a single puller wire.

Some catheter designs require more than one puller wire. For example, ifa bidirectional catheter is desired, i.e., a catheter that can bedeflected in more than one direction without rotating the catheter body,more than one puller wire becomes necessary. Catheters having two ormore puller wires and handles for controlling the multiple puller wiresare disclosed, for example, in U.S. Pat. Nos. 6,171,277 and 6,183,463.However, these patents describe catheter handles whereby simultaneousproximal movement of the puller wires relative to the catheter body isprohibited, which is desirable for certain applications. However, forother applications, it is desirable to simultaneously move the pullerwires proximally relative to the catheter body.

SUMMARY OF THE INVENTION

The present invention is directed to a dual function catheter handlethat is capable of simultaneously moving two control or puller wiresrelative to the body of the catheter and also to a catheterincorporating the handle. In one embodiment, the invention is directedto a catheter handle comprising a handle housing having proximal anddistal ends and a generally hollow interior. A first moveable member isprovided having a proximal end mounted in the interior of the handlehousing and a distal end extending outside the handle housing. The firstmoveable member is longitudinally moveable relative to the handlehousing. A second moveable member is mounted in the interior of thehandle housing and longitudinally moveable relative to the handlehousing. A rotatable member is mounted on the handle housing so thatrotation of the rotatable member causes longitudinal movement of thesecond moveable member.

In a particularly preferred embodiment, the invention is directed to acatheter handle comprising a handle housing having proximal and distalends and a generally hollow interior. A core is mounted in the interiorof the handle housing, the core having a longitudinal slot therethrough.A first moveable member is provided having a proximal end mounted in theinterior of the handle housing and a distal end extending outside thehandle housing. The first moveable member is longitudinally moveablerelative to the handle housing. A second moveable member is mounted inthe longitudinal slot of the core and is longitudinally moveablerelative to the core and handle housing. The second moveable member hasa threaded surface. A rotatable member is mounted on the handle housingand has a threaded inner surface that mates with the threaded surface ofthe second moveable member. Rotation of the rotatable member causeslongitudinal movement of the second moveable member.

In another embodiment, the invention is directed to a catheterincorporating the inventive handle. The catheter comprises an elongated,flexible catheter body having proximal and distal ends and a lumenextending therethrough. An intermediate section is mounted at the distalend of the catheter body. The intermediate section has proximal anddistal ends and first and second off-axis lumens extending therethrough.The intermediate section can be separate from or integral with thecatheter body. A handle as described above is mounted at the proximalend of the catheter body. The catheter body is attached to the handlehousing, either directly or indirectly, for example, by mounting it tothe core. A first puller wire extends through the catheter body andfirst off-axis lumen of the intermediate section. The first puller wirehas a proximal end anchored to the first moveable member of the handleand a distal end anchored at or near the distal end of the catheter. Thedistal end of the catheter to which the puller wires are anchored caninclude any part of the distal end that is inserted into the heart, suchas the intermediate section or another ablation or mapping assembly thatis mounted onto the intermediate section. A second puller wire extendsthrough the catheter body and second off-axis lumen of the intermediatesection. The second puller wire has a proximal end anchored to thesecond moveable member of the handle and a distal end anchored at ornear the distal end of the catheter. In a particularly preferredembodiment, the distal end of the first puller wire is anchored to theintermediate section and the catheter further comprises a generallycircular mapping assembly mounted on distal end of the intermediatesection, wherein the distal end of the second puller wire extendsthrough an off-axis lumen of them mapping assembly and is anchored at ornear the distal end of the mapping assembly for contraction of themapping assembly.

DESCRIPTION OF THE DRAWINGS

These and other features and advantages of the present invention will bebetter understood by reference to the following detailed descriptionwhen considered in conjunction with the accompanying drawings wherein:

FIG. 1 is a perspective view of a catheter according to the invention.

FIG. 2 is a side cross-sectional view of the catheter body of a catheteraccording to the invention.

FIG. 3 is a side cross-sectional view of the junction of theintermediate section and mapping assembly of a catheter according to theinvention.

FIG. 4 is a schematic perspective view of the mapping assembly accordingto the invention.

FIG. 5 is a side view of the mapping assembly according to the inventionin a clockwise formation.

FIG. 6 is a side view of the mapping assembly according to the inventionin a counterclockwise formation rotated 90° relative to the assemblydepicted in FIG. 5.

FIG. 7 is a schematic view of the mapping assembly according to theinvention.

FIG. 8 is a schematic view of the mapping assembly according to theinvention depicting the relationship between the first and lastelectrodes.

FIG. 9 is a side section view of a catheter handle according to theinvention.

FIG. 10 is a cut away view of the catheter handle of FIG. 9.

FIG. 11 is a perspective view of an assembly of the catheter handle ofFIG. 9.

FIG. 12 is a perspective view of the piston of the catheter handle ofFIG. 9.

DETAILED DESCRIPTION OF THE INVENTION

The invention is directed to a catheter handle for manipulating twoindependently displaceable control or puller wires. FIG. 1 shows acatheter 10 comprising an elongated catheter body 12 having proximal anddistal ends, a control handle 16 attached at the proximal end of thecatheter body, an intermediate section 14 attached at the distal end ofthe catheter body, and a mapping assembly 17 attached to theintermediate section.

With reference to FIG. 2, the catheter body 12 comprises an elongatedtubular construction having a single, axial or central lumen 18,although multiple lumens can be provided if desired. The catheter body12 is flexible, i.e., bendable, but substantially non-compressible alongits length. The catheter body 12 can be of any suitable construction andmade of any suitable material. A presently preferred constructioncomprises an outer wall 20 made of polyurethane or PEBAX. The outer wall20 comprises an imbedded braided mesh of stainless steel or the like toincrease torsional stiffness of the catheter body 12 so that, when thecontrol handle 16 is rotated, the intermediate section 14 of thecatheter 10 will rotate in a corresponding manner.

The outer diameter of the catheter body 12 is not critical, but ispreferably no more than about 8 french, more preferably about 7 french.Likewise the thickness of the outer wall 20 is not critical, but is thinenough so that the central lumen 18 can accommodate a puller wire, leadwires, and any other desired wires, cables or tubes, as discussed inmore detail below. If desired, the inner surface of the outer wall 20may be lined with a stiffening tube (not shown) to provide improvedtorsional stability. A particularly preferred catheter has an outer wall20 with an outer diameter of from about 0.090 inch to about 0.94 inchand an inner diameter of from about 0.061 inch to about 0.065 inch.

As shown in FIGS. 2 and 3, the intermediate section 14 comprises a shortsection of tubing 22 having three off-axis lumens, a first lumen 30 thatcarries a first puller wire 64, a second lumen 32 that carries a secondpuller wire 65 and a third lumen 34 that carries electrode lead wires 50and a support member 24 for the mapping assembly 17, all of which arediscussed further below. The tubing 22 is made of a suitable non-toxicmaterial that is preferably more flexible than the catheter body 12. Apresently preferred material for the tubing 22 is braided polyurethane,i.e., polyurethane with an embedded mesh of braided stainless steel orthe like. The size of each lumen is not critical, but is sufficient tohouse the lead wires, puller wire or support member.

The useful length of the catheter, i.e., that portion that can beinserted into the patient excluding the mapping assembly 17, can vary asdesired. Preferably the useful length ranges from about 110 cm to about120 cm. The length of the intermediate section 14 is a relatively smallportion of the useful length, and preferably ranges from about 3.5 cm toabout 10 cm, more preferably from about 5 cm to about 6.5 cm.

A preferred means for attaching the catheter body 12 to the intermediatesection 14 is illustrated in FIG. 2. The proximal end of theintermediate section 14 comprises an outer circumferential notch 26 thatreceives the inner surface of the outer wall 22 of the catheter body 12.The intermediate section 14 and catheter body 12 are attached by glue orthe like.

Alternatively, the catheter body 12 and intermediate section 14 can beformed of a single unitary piece of tubing. Such a design would beuseful, for example, where the catheter body and intermediate sectionhave the same number of lumens.

If desired, a spacer (not shown) can be located within the catheter body12 between the distal end of the stiffening tube (if provided) and theproximal end of the intermediate section 14. The spacer provides atransition in flexibility at the junction of the catheter body 12 andintermediate section 14, which allows this junction to bend smoothlywithout folding or kinking. A catheter having such a spacer is describedin U.S. Pat. No. 5,964,757, the disclosure of which is incorporatedherein by reference.

At the distal end of the intermediate section 14 is a mapping assembly,as shown in FIGS. 3 to 7. The mapping assembly comprises anon-conductive covering 28 having two off-axis lumens 114 and 116extending therethrough. The distal end of the support member 24, whichgives shape to the mapping assembly 17, extends through the first lumen114 of the non-conductive covering 28. However, if desired, the supportmember 24 can be eliminated and the non-conductive covering 28 can bedesigned to provide the desired shape for the mapping assembly 17.

The mapping assembly 17 has a generally straight proximal region 38, agenerally circular main region 39 and a generally straight distal region40. The proximal region 38 is mounted on the intermediate section 14, asdescribed in more detail below, so that its axis is generally parallelto the axis of the intermediate section. The proximal region 38preferably has an exposed length, e.g., not contained within theintermediate section 14, ranging from about 3 mm to about 12 mm, morepreferably about 3 mm to about 8 mm, still more preferably about 5 mminch, but can vary as desired.

The generally circular main region 39 does not form a flat circle, butis very slightly helical, as shown in FIGS. 4 to 6. The main region 39has an outer diameter preferably ranging from about 8 mm to about 35 mm,more preferably from about 12 mm to about 20 mm, still more preferablyabout 15 mm. The transition region 41 of the straight proximal region 38and generally circular main region 39 is slightly curved and formed suchthat, when viewed from the side with the proximal region at the top ofthe circular main region as shown in FIG. 5, the proximal region (alongwith the intermediate section 14) forms an angle α with the curvedregion ranging from about 75° to about 95°, preferably from about 83° toabout 93°, more preferably about 87°. The main region 39 can curve in aclockwise direction, as shown in FIG. 5, or a counterclockwisedirection, as shown in FIG. 6. When the assembly 17 is turned 90°, asshown in FIG. 6, so that the transition region 41 is near the center ofthe main region, the proximal region (along with the intermediatesection 14) forms an angle β with the main region ranging from about90°to about 135°, preferably from about 100° to about 110°, morepreferably about 105°.

The support member 24 is made of a material having shape memory, i.e.,that can be straightened or bent out of its original shape upon exertionof a force and is capable of substantially returning to its originalshape upon removal of the force. A particularly preferred material forthe support member 24 is a nickel/titanium alloy. Such alloys typicallycomprise about 55% nickel and 45% titanium, but may comprise from about54% to about 57% nickel with the balance being titanium. A preferrednickel/titanium alloy is Nitinol, which has excellent shape memory,together with ductility, strength, corrosion resistance, electricalresistivity and temperature stability. The non-conductive covering 28can be made of any suitable material, and is preferably made of abiocompatible plastic such as polyurethane or PEBAX.

A series of ring electrodes 36 are mounted on the non-conductivecovering 28 of the generally circular main region 39 of the mappingassembly 17. The ring electrodes 36 can be made of any suitable solidconductive material, such as platinum or gold, preferably a combinationof platinum and iridium, and mounted onto the non-conductive covering 28with glue or the like. Alternatively, the ring electrodes can be formedby coating the non-conductive covering 28 with an electricallyconducting material, like platinum, gold and/or iridium. The coating canbe applied using sputtering, ion beam deposition or an equivalenttechnique.

In a preferred embodiment, each ring electrode 36 is mounted by firstforming a hole in the non-conductive covering 28. An electrode lead wire50 is fed through the hole, and the ring electrode 36 is welded in placeover the lead wire and non-conductive covering 28. The lead wires 50extend between the non-conductive covering 28 and the support member 24.

The number of ring electrodes 36 on the assembly can vary as desired.Preferably the number of ring electrodes ranges from about six to abouttwenty, more preferably from about eight to about twelve. In aparticularly preferred embodiment, the assembly carries ten ringelectrodes. The ring electrodes 36 are preferably approximately evenlyspaced around the generally circular main region 39, as best shown inFIG. 7. In a particularly preferred embodiment, a distance ofapproximately 5 mm is provided between the centers of the ringelectrodes 36.

FIGS. 7 and 8 show a particularly preferred electrode arrangement. Asexplained above, the generally circular main region 39 is very slightlyhelical, although FIGS. 7 and 8 depict the main region as a flat circle,as it would generally appear when viewed from the distal end of thecatheter. The generally straight distal region 40 forms a tangentrelative to the generally circular main region 39 and contacts the mainregion at a tangent point 43. A first electrode 36 a is provided, whichis the electrode that is on the generally circular main region 39closest to the proximal region 38. A second electrode 36 b is provided,which is the electrode that is on the generally circular main region 39closest to the distal region 40. Preferably, the first electrode 36 a ispositioned along the circumference of the generally circular main region39 at a distance θ of no more than about 55° from the tangent point,more preferably no more than about 48° from the tangent point, stillmore preferably from about 15° to about 36° from the tangent point.

Preferably the second electrode 36 b is positioned along thecircumference of the generally circular main region 39 at a distance ωof no more than about 55° degrees from the tangent point, morepreferably no more than about 48° from the tangent point, still morepreferably from about 15°to about 36° from the tangent point. Preferablythe first electrode 36 a is positioned along the circumference of thegenerally circular main region 39 at a distance γ of no more than 100°from the second electrode 36 b, preferably no more than 80° from thesecond electrode, still more preferably from about 30° to about 75° fromthe second electrode. If desired, additional electrodes (not shown)could be mounted along the intermediate section 14, the generallystraight proximal section 39, the transition region 41, and/or generallystraight distal region 40.

The junction of the intermediate section 14 and mapping assembly 17 isshown in FIG. 3. The non-conductive covering 28 is attached to thetubing 22 of the intermediate section by glue or the like. The supportmember 24 extends from the third lumen 34 into the first lumen 114 ofthe non-conductive covering 28 and through the generally circular mainregion 39 of the mapping assembly. The proximal end of the supportmember 24 terminates a short distance within the third lumen 34 of theintermediate section 14, approximately about 5 mm, so as not toadversely affect the ability of the intermediate section to deflect.However, if desired, the proximal end of the support member 24 canextend into the catheter body 12.

The lead wires 50 attached to the ring electrodes 36 also extend throughthe first lumen 114 in the non-conductive covering 28, the third lumen34 of the intermediate section 14, the central lumen 18 of the catheterbody 12, and the control handle 16, and terminate at their proximal endin the connector 37, which is connected to a source of RF energy (notshown). The portion of the lead wires 50 extending through the centrallumen 18 of the catheter body 12, control handle 16 and proximal end ofthe intermediate section 14 are enclosed within a protective sheath 62,which can be made of any suitable material, preferably polyimide. Theprotective sheath 62 is anchored at its distal end to the proximal endof the intermediate section 14 by gluing it in the third lumen 34 withpolyurethane glue or the like.

The generally straight distal region 40 of the mapping assembly 17 isprovided with an atraumatic design to prevent the distal end of themapping assembly from penetrating tissue. In the depicted embodiment,the distal region 40 comprises a tightly wound coil spring 44 made, forexample, of stainless steel, such as the mini guidewire commerciallyavailable from Cordis Corporation (Miami, Fla.) or a coil having a0.0045 inch wire size and a 0.009 inch inner diameter, such as thatcommercially available from Microspring. The coil spring 44 extendsthrough the first lumen 114 of the non-conductive covering 28 and ismounted at its proximal end in a short piece of tubing 45 withpolyurethane glue or the like, which is then glued or otherwise anchoredwithin the non-conductive covering. The tubing 45 is less flexible thanthe non-conductive covering 28 but more flexible than that supportmember 24 to provide a transition in flexibility along the length of themapping assembly 17. The distal end of the distal region 40 is capped,preferably with polyurethane glue 46, to prevent body fluids fromentering the mapping assembly 17. In the depicted embodiment, thegenerally straight distal region 40 has a length of about 0.5 inch, butcan be any desired length, for example, ranging from about 0.25 inch toabout 1.0 inch. The generally straight distal region 40 is preferablysufficiently long to serve as an anchor for introducing the catheterinto a guiding sheath, as discussed in more detail below, because themapping assembly 17 must be straightened upon introduction into thesheath. Without having the generally straight distal region 40 as ananchor, the mapping assembly 17 has a tendency to pull out of theguiding sheath upon its introduction into the guiding sheath.Additionally, if desired, the distal region 40 can be formed, at leastin part, of a radiopaque material to aid in the positioning of themapping assembly 17 under fluoroscopy.

As noted above, two puller wires 64 and 65 extend through the catheter.The first puller wire 64 is provided for deflection of the intermediatesection 14. The second puller wire 65 is provided for contracting themapping assembly 17. Each puller wire 64 and 65 extends from the controlhandle 16, through the central lumen 18 of the catheter body 12 and intothe first and second lumens 30 and 32 of the intermediate section 14,respectively. The second puller wire 65 then extends into the secondlumen 116 of the mapping assembly 17. As described in more detail below,the proximal end of the first puller wire 64 is anchored within thecontrol handle 16, and the distal end of the first puller wire isanchored in the intermediate section 14. Also as described furtherbelow, the proximal end of the second puller wire 65 is anchored withinthe control handle 16, and the distal end of the second puller wire isanchored in the distal end of the mapping assembly 17.

Each puller wire 64 and 65 is made of any suitable metal, such asstainless steel or Nitinol. Preferably each puller wire 64 and 65 has acoating (not shown), such as a coating of Teflon or the like. Eachpuller wire 64 and 65 has a diameter preferably ranging from about 0.006inch to about 0.010 inch.

In the depicted embodiment, the first puller wire 64 is anchored at itsdistal end to the distal end of the intermediate section 14 using aT-shaped anchor, as shown in FIG. 3, which comprises a short piece oftubular stainless steel 80, e.g., hypodermic stock, which is fitted overthe distal end of the first puller wire 64 and crimped to fixedly secureit to the first puller wire. The distal end of the tubular stainlesssteel 80 is fixedly attached, e.g., by welding, to a cross-piece 82formed of stainless steel ribbon or the like. The cross-piece 82 sitsbeyond the distal end of the first lumen 30. The cross-piece 82 islarger than the lumen opening and, therefore, cannot be pulled throughthe opening. The distal end of the first lumen 30 is then filled withglue or the like, preferably a polyurethane glue. Within the first lumen30 of the intermediate section 14, the first puller wire 64 extendsthrough a plastic, preferably Teflon®, puller wire sheath (not shown),which prevents the first puller wire 64 from cutting into the wall ofthe intermediate section 14 when the intermediate section is deflected.Alternatively, the first puller wire 64 could be anchored to the sidewall of the intermediate section 14 in a similar manner, where theT-shaped anchor extends into a notch in the side wall rather than beyondthe distal end of the first lumen 30. Such a design is disclosed in U.S.Pat. No. 6,064,908, the disclosure of which is incorporated herein byreference.

The second puller wire 65 is anchored in the distal end of the secondlumen 116 of the mapping assembly in a manner similar to the firstpuller wire 64. A T-shaped anchor is mounted on the distal end of thesecond puller wire 65, extends into a notch in the side wall of thenon-conductive covering 28, and is held in place with polyurethane glueor the like. Any other suitable method for anchoring the puller wires 64and 65 could also be used.

In the depicted embodiment, two compression coils 66 are situated withinthe catheter body 12, each in surrounding relation to a correspondingpuller wire 64 and 65. Each compression coil 66 extends from theproximal end of the catheter body 12 to the proximal end of theintermediate section 14. The compression coils 66 are made of anysuitable metal, preferably stainless steel. Each compression coil 66 istightly wound on itself to provide flexibility, i.e., bending, but toresist compression. The inner diameter of each compression coil 66 ispreferably slightly larger than the diameter of the corresponding pullerwire 64 and 65. The Teflon® coatings on the puller wire 64 allow them toslide freely within the compression coils 66. The outer surfaces of thecompression coil 66 are covered by flexible, non-conductive sheathes 68,e.g., made of polyimide tubing.

Each compression coil 66 is anchored at its proximal end to the outerwall 20 of the catheter body 12 by proximal glue joint 70 and at itsdistal end to the intermediate section 14 by distal glue joint 72. Bothglue joints 70 and 72 preferably comprise polyurethane glue or the like.The glue may be applied by means of a syringe or the like through a holemade between the outer surface of the catheter body 12 and the centrallumen 18. Such a hole may be formed, for example, by a needle or thelike that punctures the outer wall 20 of the catheter body 12 which isheated sufficiently to form a permanent hole. The glue is thenintroduced through the hole to the outer surfaces of the compressioncoils 66 and wicks around the outer circumferences to form a glue jointabout the entire circumferences of the compression coils. If desired,the compression coils 66 could be anchored at different longitudinallocations or eliminated altogether.

Longitudinal movement of each of the puller wires 64 and 65 relative tothe catheter body 12 is accomplished by suitable manipulation of thecontrol handle 16. An embodiment of the control handle 16 according tothe invention is shown in FIGS. 9 to 11. The control handle 16 comprisesa generally tubular housing 86 having a longitudinal axis and proximaland distal ends and a generally tubular core 90 extending within thehousing along its longitudinal axis. In the depicted embodiment, thecore 90 is a separate piece that is fixedly attached to the handlehousing 86 for ease in manufacturing, although the core could be formedintegral with the housing if desired. The core 90 has proximal anddistal ends that extend beyond and outside the proximal and distal ends,respectively, of the housing 86. The catheter body 12 is fixedlyattached to the distal end of the core 90 by means of a glue joint andshrink sleeve, as is generally known to those skilled in the art, or byany other suitable method. The puller wires 64 and 65, lead wires 50 andany other wires, tubes or cables that extend through the catheter body12 extend through a lumen or passage 88 in the core 90, although thelead wires 50 are not shown in FIGS. 9 to 11 for clarity. An elongatedslot 102 extends through a portion of the length of the core 90.

A piston 84 is mounted within the housing 86 in surrounding relation tothe core 90. The piston 84 has a tubular distal end 85 and asemicircular proximal end 87. The semicircular proximal end 87 is shapedso that its inner surface fits generally against the tubular core 102.The precise shape of the piston 84 is not critical to the invention.When the handle 16 is assembled, a portion of the distal end 85 of thepiston 84 extends outside the distal end of the handle housing 86. Thedistal end 85 of the piston 84 comprises threading 89 to provide a meansfor mounting a thumb control 92, having corresponding internal threading(not shown), onto the piston. A preferred arrangement for mounting thethumb control 92 on the piston 84 is described in U.S. patentapplication Ser. No. 09/546,310 filed Apr. 10, 2000, entitled “SingleGear Drive Bi-Directional Control Handle for Steerable Catheter,” thedisclosure of which is incorporated herein by reference. With thisdesign, the user can cause longitudinal movement of the piston 84relative to the handle housing 86 by pushing or pulling the piston 84(directly or via the thumb control 92).

The proximal end of the first puller wire 64 is anchored to the piston84 by any suitable method. In the depicted embodiment, as shown in FIG.12, the proximal end of the piston 84 comprises a generally rectangularopening 118 having a slanted edge 119. The opening 118 extends through awall of the piston 84. A channel 121, which only extends a part of theway through the wall of the piston 84, is provided proximal the opening118. A small groove 122 having a width less than that of the channel 121connects the channel to the opening 118. The first puller wire 64extends through the lumen 88 in the core 90, through the slot 102 in thecore, through the opening 118 in the piston 84, through the small groove122, and into the channel 121. The first puller wire 64 is anchored inthe channel 121 by means of a puller wire anchor 124, which preferablycomprises a short piece of hypodermic stock that is fixedly attached,e.g., by crimping, to the proximal end of the first puller wire 64 afterit has passed through the small groove 122. The puller wire anchor 124has a diameter greater than the width of the small groove 122 and thusprevents the proximal end of the first puller wire 64 from being pulledthrough the small groove. The length of the opening 118 is limited suchthat, when the piston 84 is in its most distal position relative to thehousing 86, the opening does not extend outside the housing. However,the opening 118 is preferably long enough so that the first puller wire64 extends through the opening at an angle rather than bending orkinking.

Because the catheter body 12 is attached to the core 90, proximalmovement of the piston 84 relative to handle housing 86 and core 90causes proximal movement of the piston and first puller wire 64 relativeto the catheter body 12. Such movement results in deflection of theintermediate section 14 in the direction of the side of the firstoff-axis lumen 30 through which the first puller wire extends.

As shown in FIG. 9, the second puller wire 65 is anchored at itsproximal end to a threaded slide 100, which is disposed in the slot 102of the core 90, by any suitable method. In the depicted embodiment, theslide 100 comprises a generally solid, generally rectangular piece ofplastic with threading 101 along one surface. The slide 100 has agenerally rectangular hole 103 in which the distal end of the secondpuller anchor 65 in anchored with a puller wire anchor 125, in a mannersimilar to the first puller wire 64, discussed above.

The threaded slide 100 is mounted within the slot 102 in the core 90such that the threaded slide is prevented from rotating, but is able tomove longitudinally within the slot, thus producing a relative lateralmotion between the threaded slide and the core. The handle housing 86has a window 104, through which the threaded surface 101 of the threadedslide 100 protrudes when the handle is assembled. The window has firstand second window edges 118 and 120, which limit the lateral movement ofthe threaded slide 100.

A threaded sleeve 98 is mounted between first and second shoulders 106and 108 on the handle housing 86. The threaded sleeve 98 has internalthreading that engages the threads 101 of the threaded slide 100, suchthat rotation of the threaded sleeve causes the threaded slide to movelongitudinally within the slot 102 in the core 90. Other arrangementsfor slidably mounting the threaded slide 100 within the handle housing86 could also be used in accordance with the invention. For example, thethreaded slide 100 could be mounted over or around the core 90 insteadof within a slot in the core.

Because the proximal end of the second puller wire 65 is attached to thethreaded slide 100 and the core 90 is attached to the catheter body 12,longitudinal movement of the threaded slide relative to the core resultsin corresponding movement of the second puller wire relative to thecatheter body. Therefore, when the threaded sleeve 98 is rotated, thesecond puller wire 65 moves proximally relative to the catheter body 12,thus causing the straight distal region 40 of the mapping assembly 17 toalso move relative to the catheter body and arc proximally or deflect.The deflection of the straight distal region 40 of the mapping assembly17, in turn, causes the circular main region 39 of the mapping assemblyto contract to thereby have a smaller diameter.

In one embodiment, the threaded sleeve 98 has a longitudinal slit andcomprises a flexible material, such as delryn. To mount the threadedsleeve 98 over the handle housing 86, the sleeve is separated along theslit and fit over the housing, such that the sleeve is disposed betweenthe shoulders 106 and 108 of the handle housing. Alternatively, thethreaded sleeve 98 may be formed from two halves that are fit over thehousing 86 and then affixed together, such as by weld, adhesive, ascrew, a rivet or the like. In the depicted embodiment, a grippingsleeve 112 is mounted over the threaded sleeve 98 to aid in rotating thesleeve and provide comfort to the user. The gripping sleeve 112 maycomprise a high friction surface, such as rubber. The gripping sleeve112 also aides in holding the threaded sleeve 98 together when thesleeve is assembled on the handle housing 86.

In the depicted embodiment, the threaded sleeve 98 goes around theentire circumference of the handle housing 86. If desired the threadedsleeve 98 could be replaced with another rotatable member that extendsaround only a part of the circumference of the handle housing 86.

If desired, a fastener (not shown) can be provided to maintain thehandle housing 86 in place over the core 90. A description of such anarrangement is provided in U.S. patent application Ser. No. 09/546,310filed Apr. 10, 2000, entitled “Single Gear Drive Bi-Directional ControlHandle for Steerable Catheter,” the disclosure of which is incorporatedherein by reference.

In use, a suitable guiding sheath is inserted into the patient with itsdistal end positioned at a desired mapping location. An example of asuitable guiding sheath for use in connection with the present inventionis the Preface™ Braiding Guiding Sheath, commercially available fromCordis Webster (Diamond Bar, Calif.). The distal end of the sheath isguided into one of the atria. A catheter in accordance with the presentinvention is fed through the guiding sheath until its distal end extendsout of the distal end of the guiding sheath. As the catheter is fedthrough the guiding sheath, the mapping assembly 17 is straightened tofit through the sheath. Once the distal end of the catheter ispositioned at the desired mapping location, the guiding sheath is pulledproximally, allowing the deflectable intermediate section 14 and mappingassembly 17 to extend outside the sheath, and the mapping assembly 17returns to its original shape due to the shape-memory of the supportmember 24. The mapping assembly 17 is then inserted into a pulmonaryvein or other tubular region (such as the coronary sinus, superior venacava, or inferior vena cava) so that the outer circumference of thegenerally circular main region 39 of the assembly is in contact with acircumference inside the tubular region. Preferably at least about 50%,more preferably at least about 70%, and still more preferably at leastabout 80% of the circumference of the generally circular main region isin contact with a circumference inside the tubular region.

The circular arrangement of the electrodes 36 permits measurement of theelectrical activity at that circumference of the tubular structure sothat ectopic beats between the electrodes can be identified. The size ofthe generally circular main region 39 permits measurement of electricalactivity along a diameter of a pulmonary vein or other tubular structureof or near the heart because the circular main region has a diametergenerally corresponding to that of a pulmonary vein or the coronarysinus. Additionally, because the main region 39 preferably does not forma flat circle, but instead is somewhat helical, as shown in FIG. 4, itis easier for the user to guide the mapping assembly 17 into a tubularregion. If the circumference of the main region 39 of the mappingassembly 17 is larger than the circumference of the structure to bemapped, the mapping assembly can be contracted by longitudinal movementof the second puller wire 65 using the control handle 16, as describedabove.

The inventive handle is not limited to the above-described catheterdesign. The handle is also particularly useful for bi-directionalcatheters and other catheters having two puller wires for deflection ofthe distal end of the catheter body, i.e., the intermediate section.Such catheters are described in U.S. Pat. Nos. 6,171,277, 6,183,463,6,198,974, 6,210,407, and 6,267,746, U.S. patent application Ser. No.09/822,087, filed Mar. 30, 2001, “Steerable Catheter with a ControlHandle Having a Pulley Mechanism,” and U.S. patent application Ser. No.09/846,732, filed Apr. 30, 2001, entitled “Asymmetrical BidirectionalSteerable Catheter,” the disclosures of which are incorporated herein byreference. Other uses for the handle of the invention would berecognized by one skilled in the art.

The preceding description has been presented with reference to presentlypreferred embodiments of the invention. Workers skilled in the art andtechnology to which this invention pertains will appreciate thatalterations and changes in the described structure may be practicedwithout meaningfully departing from the principal, spirit and scope ofthis invention.

Accordingly, the foregoing description should not be read as pertainingonly to the precise structures described and illustrated in theaccompanying drawings, but rather should be read consistent with and assupport to the following claims which are to have their fullest and fairscope.

1. A catheter comprising: an elongated, flexible catheter body havingproximal and distal ends and a lumen extending therethrough; anintermediate section at the distal end of the catheter body havingproximal and distal ends and first and second off-axis lumens extendingtherethrough; a handle mounted at the proximal end of the catheter body,the handle comprising: a handle housing having proximal and distal endsand generally hollow interior, whereby the catheter body is attached tothe handle housing, a first moveable member having a proximal endmounted in the interior of the handle housing and a distal end extendingoutside the handle housing, the first moveable member beinglongitudinally moveable relative to the handle housing, and a secondmoveable member mounted in the interior of the handle housing andlongitudinally moveable relative to the handle housing; and a rotatablemember mounted on the handle housing, whereby rotation of the rotatablemember causes longitudinal movement of the second moveable member; afirst puller wire extending through the catheter body and first off-axislumen of the intermediate section, having a proximal end anchored to thefirst moveable member of the handle, and having a distal end anchored ator near the distal end of the catheter; and a second puller wireextending through the catheter body and second off-axis lumen of theintermediate section, having a proximal end anchored to the secondmoveable member of the handle, and having a distal end anchored at ornear the distal end of the catheter.
 2. The catheter of claim 1, whereinthe distal end of the first puller wire is anchored to the intermediatesection.
 3. The catheter of claim 1, further comprising a generallycircular mapping assembly mounted on the distal end of the intermediatesection and having proximal and distal ends and an off-axis lumenextending therethrough, wherein the distal end of the second puller wireextends through the off-axis lumen of the mapping assembly and isanchored at or near the distal end of the mapping assembly.
 4. Thecatheter of claim 1, wherein the first moveable member and secondmoveable member are capable of simultaneously moving proximally relativeto the handle housing.
 5. The catheter of claim 1, wherein the rotatablemember has a threaded inner surface that mates with a threaded surfaceof the second moveable member.
 6. The catheter of claim 5, wherein thecatheter handle further comprises a core mounted in the interior of thehandle housing, the core having a longitudinal slot therethrough inwhich the second moveable member is slidably mounted.
 7. The catheter ofclaim 1, wherein the catheter handle further comprises a core mounted inthe interior of the handle housing, the core having a longitudinal slottherethrough in which the second moveable member is slidably mounted. 8.The catheter of claim 7, wherein the first moveable member is generallytubular and is mounted in surrounding relation to a portion of the core.9. The catheter of claim 3, wherein longitudinal movement of the firstpuller wire results in deflection of the intermediate section, andlongitudinal movement of the second puller wire results in contractionof the generally circular mapping assembly.